Drainpipes invariably receive solids along with the waste liquids to be drained. A common plugging condition in typical households is caused from hair collecting in the drainpipes and eventually clogging the pipe.
Typical drain installations include a "trap" which is a sharply bent section of pipe. Traps are used to prevent gases from escaping back upwardly through the drainpipe to exit out the drain opening in the adjacent sink or tub. Drainpipes usually include a removable trap to facilitate cleaning. The trap must be removed for this purpose--a task not lightly undertaken by the typical homeowner. Furthermore, not all drain stoppages occur within the drain trap. Stoppage may occur away from the trap. When this happens, further measures must be taken to unplug the drain. Various chemicals and apparatus have been developed for this purpose. Perhaps the most common mechanical device is the "snake". A "snake" is an elongated wound wire that is sufficiently flexible to be guided through the drain and trap, seeking a clogged area. The snake is usually turned by hand or by an appropriate electric motor as it is fed into the drain. Snakes often require removal of the trap before they will function effectively.
Chemicals have been advertised to "dissolve" clogs in pipelines. But it is not unusual for the same chemicals to have a caustic, damaging effect on the associated plumbing.
Some drain traps are supplied with cleanout plugs. The plug can be removed and appropriate apparatus inserted through the plug hole to clean out the trap area. Other devices have been developed for stopping and accumulating solids within the drain trap area.
U.S. Pat. No. 4,230,582 discloses such a drain trap that includes a removable strainer means. A bottom section of the trap is removable to allow access to the straining device. It is pointed out that this is a complete trap arrangement and installation requires removal of the old drain trap and replacement with the trap including the integral cleanout.
Another somewhat similar trap arrangement is shown in U.S. Pat. No. 4,179,762. A tubular section of the trap is provided with a strainer attached to a threaded cap. The strainer fits through a tubular section of the trap and the cap is threadably engaged to one end of the tube section. A perforated disk is used as the strainer for collecting solid materials within one side of the trap.
U.S. Pat. No. 4,164,048 discloses another form of specialized drain trap including an angular flange that releasably receives a straining screen. The screen is removable through a cap threadably attached to the flange. The screen strains solids from the trap area.
Another trap arrangement is illustrated in U.S. Pat. No. 3,935,602. Again, this is a specialized trap assembly having a removable bottom section with an insertable strainer mounted therein. The strainer makes use of spaced sets of bristles to collect solids.
U.S. Pat. No. 1,217,763 shows another specialized trap arrangement wherein the plurality of bristles are arranged in a spiral fashion along a central shaft removably located within a section of the trap. The bristles are intended to collect solids in the trap area and can be removed for cleaning.
Another form of drain trap is shown in U.S. Pat. No. 4,301,554. Here a separate trap is provided with an integral, removable cleanout structure attached thereto. The cleanout includes removable straining fingers for collecting and removing solids from the draining waste liquids.
The above arrangements are directed primarily to the trap area of drainpipes and require either extensive modification to the drain trap or complete replacement thereof.
U.S. Pat. No. 3,959,831 discloses a number of stacked disks including radially extending bristles. These disks can be attached to a drain plug shank for the purpose of accumulating hairs and other solid particulates before the waste liquid reaches the trap.
A need remains for a device that will fit within the drainpipe at any convenient location for effectively straining drainage liquids and that can be easily removed for cleanout purposes. It is further desirable to obtain such a device that can be easily mounted to existing drainpipe structures without requiring extensive modification.